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G L Tarolo

Publications and source records attributed to G L Tarolo.

At least 37 records · Page 2Linked to original sources
PubMed1996

Assessment of myocardial area at risk by technetium-99m sestamibi during coronary artery occlusion: comparison between three tomographic methods of quantification.

The aim of this study was to directly compare three currently used quantitative methods of analysis of technetium-99m sestamibi images in patients with selective balloon-induced transmural ischaemia. The area at risk (AR) was assessed in 19 patients undergoing single-vessel percutaneous transluminal coronary angioplasty by injecting the 99mTc-sestamibi at the time of coronary artery occlusion during balloon inflation. After imaging, the patients were classified according to localization of the perfusion defect as having anteroseptal (group I, 11 patients) or posterolateral defects (group II, eight patients). The planimetric technique based on polar maps, proposed by Verani et al. (J Am Coll Cardiol, 1988) (method A), the method described by Tamaki et al. (Circulation, 1982) (method B) and the technique validated by O Connor et al. (Eur J Nucl Med, 1990) (method C) were tested. Three threshold values of 45%, 50% and 60% of the maximum left ventricular count were used to define the limits of the perfusion defect. The mean values of the AR calculated by the three techniques with the original cut-off level (method A=16.5%+/-12.9; method B=10.4%+/-7.6%; method C=29.6%+/-15.7%) were statistically different (one-way analysis of variance: P<0.001; paired t test: method A vs B, P=0.003; method B vs C and method A vs C, P<0.0001). There was no significant difference between the mean values of the AR estimated by the three methods using the same cut-off levels. The use of 60% of the maximum left ventricular count provided the best correlation between the techniques (method A vs B, r=0.95; method B vs C, r=0.92; method A vs C, r=0.95). Nevertheless, a difference >10% between the values of AR assessed by the three methods was found in four subjects. There was no significant difference between the three methods in the evaluation of AR in the subjects of group I and group II. Reproducibility was good for all methods. It is concluded that the three methods of analysis of the AR by 99mTc-sestamibi SPET imaging showed comparable performance and good reproducibility using the same cut-off level. The location of perfusion defect does not affect the comparability of the three techniques. We suggest the use of a cut-off level of 60% for all three methods in the assessment of the AR by 99mTc-sestamibi SPET imaging.

Angioplasty, Balloon, Coronary↗
PubMed1996

Nuclear cardiology and echocardiography for the assessment of myocardial viability.

The review aims to make a comparative analysis of the nuclear cardiology and echocardiographic approaches for the assessment of myocardial viability on the basis of the most recent literature. Preliminarily the most extensively used methods are described: 1) metabolic tracers, especially as regards FDG-F18 (quantitative uptake; mismatch FDG uptake/perfusion); 2) sarcolemmal integrity tracers (201Tl- with stress-redistribution-reinjection or with rest-redistribution protocols; rest MIBI 99mTc); 3) low dose dobutamine stress echocardiography (LDDSE) for the detection of residual contractility reserve. Global sensitivity values of thallium studies are reported to be similar to those of LDDSE, but in selected patients populations with akinetic or severely hypokinetic segments the LDDSE sensitivity seems to be significantly lower, when metabolic viability assessed by FDG studies is assumed as gold standard. According to the Authors' opinion thallium study with a protocol including a rest injestion can be considered at the moment the first choice for myocardial viability assessment because of its convenience, reproducibility, possibility of technical and interpretative standardization, amount of clinical and experimental validations. Anyway further clinical trials with adequate follow-up are necessary in order to define the scintigraphic and echocardiographic patterns that provide the best accuracy in the prediction of the post-revascularization clinical outcome.

Coronary Disease↗
PubMed1995

Lung uptake of 201Tl in myocardial stress imaging: correlation with echocardiographic and scintigraphic variables of myocardial ischaemia.

The lung uptake of thallium-201 (201Tl) in planar imaging was evaluated in 384 patients enrolled in the SIRT study (Italian Multicentre Study on Thallium Reinjection). All patients underwent treadmill exercise, and at peak exercise 74 MBq of 201TI were injected. The patients were then evaluated after reinjection of 201Tl under baseline conditions. The left ventricle was subdivided into 16 echocardiographic and 15 scintigraphic segments. The best correlates of visually scored 201Tl lung uptake, of the lung heart ratio and lung wash-out were checked. The independent variables entered in the stepwise multiple-regression analysis were: the echocardiographic wall motion index, the scintigraphic perfusion score index, and the number of segments that improved by at least 1 and 2 grades after redistribution and after reinjection. We concluded that the lung:heart ratio and, in particular, lung wash-out do not correlate more closely than the visual score with the variables taken into consideration. This suggests that visually scored lung uptake of 201Tl is still of value in nuclear cardiology practice. The scintigraphic variables associated with reinjection do not seem to offer any additional information with respect to redistribution variables. We also analysed the impact on 201Tl lung uptake of several other index variables. Student's t-test revealed that no single variable significantly alters lung uptake after stress testing.

Adult↗
PubMed1994

A multicenter trial on interobserver and intraobserver reproducibility of segmental scoring of thallium-201 planar myocardial imaging before and after reinjection. Italian Group of Nuclear Cardiology.

UNLABELLED: Inter- and intraobserver reproducibility (R) of segmental 201Tl scores after stress (ST), redistribution (RD) and reinjection (RI) planar imaging were evaluated. METHODS: Images were examined from 396 patients with suspected coronary artery disease, demonstrated by means of post-ST imaging of at least one perfusion defect. To eliminate external sources of variability, the same gamma camera, acquisition protocol and computer software were used in this multicenter study. Thallium-201 images of the anterior, left anterior oblique and left lateral projections were obtained immediately, 4 hr after exercise and 30 min after the injection of additional 201Tl either on the same day or on a different day. The left ventricle was divided into 15 segments and evaluated by three independent observers, blinded to clinical data, according to a five-point scale. RESULTS: The R score for ST, RD and RI images, expressed as an intraclass correlation coefficient, was 0.76, 0.74 and 0.72, respectively. After averaging multiple observer scores, R increased to 0.91, 0.90 and 0.89, respectively. Individual observer measurement of the R score was 0.48, 0.51 and 0.32 for ST-RD, ST-RI and RD-RI image pairs, respectively, and multiple observer scores showed R increases to 0.74, 0.76 and 0.58. CONCLUSION: This qualitative scale reliably assesses the severity of 201Tl perfusion defects, particularly when multiple-observer scores are averaged. Individual observer change scores should be taken with great caution, especially in studies involving the visual evaluation of RD-RI image changes.

Coronary Disease↗
PubMed1993

Fourier amplitude image circumferential profile analysis in the evaluation of the dipyridamole test.

The aim of this study was to evaluate a circumferential profile method of analysis (CPA) of the Fourier image of amplitude (FA), obtained by equilibrium gated radionuclide angiocardiography (EGRA) in the assessment of the response to the dipyridamole (DIP) test in patients with previous myocardial infarction. The changes in regional wall motion (RWM) induced by DIP in a group of 29 patients with previous MI were compared with those of a ten-patient control group. On the basis of SPECT thallium-201 standard stress-rest scintigraphy the infarcted patients were divided into 9 patients with fixed perfusion defects at four hours and 20 patients with both fixed and reversible perfusion defects. The quantitative CPA was carried out on the FA image normalized by the mean amplitude calculated for the left ventricle (LV) area. A circular ROI was drawn around the FA left ventricle image and two curves (basal and post-DIP) with 60 points were obtained. We compared this method with a five-sector method of analysis applied to the same FA images. An increase of 2 or more SD in the basal post-DIP ratio curve, compared with the average of the ratios in the control group, was found in 16 of 20 patients with reversible perfusion defects (sensitivity: 80%) and an increase in the same ratio was found in 2 of 9 MI patients with fixed perfusion defects (specificity: 78%). A sensitivity and specificity of 60% and 78% respectively were found using sectorial analysis.

Adult↗
PubMed1993

Thallium-201 lung uptake: comparison of an automatic and a manual method of ROI drawing.

An automatic method for ROI drawing to measure 201TI lung uptake after stress testing in planar and tomographic myocardial perfusion imaging, was compared with the more commonly used manual method. A linear correlation in the lung/heart ratio (LHR) and lung washout (LWO) data, obtained in planar and SPECT images with the two methods, was found. Pearson's correlation coefficient between the automatic and manual methods was highly significant both for LHR and for LWO. For LHR we found a high linear correlation between the two methods in the planar anterior (r = 0.71, p < 0.001), SPECT anterior (r = 0.84, p < 0.001), and SPECT LAO (r = 0.96, p < 0.001) views. The analysis of LWO data showed a good linear correlation for the planar anterior (r = 0.84, p < 0.001), SPECT anterior (r = 0.66, p < 0.005) and SPECT LAO (r = 0.79, p < 0.001) views. Furthermore, comparison by the student's t test of the averages of the LHR and LWO values obtained in the same views but with different methods was performed. The advantages and the critical issues associated with the automatic method are discussed; it appears to be quick and easy to perform and to be equivalent to the more time-consuming method based on a manual definition of left lung ROI.

Adult↗
PubMed1993

Delayed effect of streptokinase on left ventricular function after acute myocardial infarction assessed by equilibrium gated radionuclide angiocardiography.

A blind comparative study was conducted on 80 consecutive patients who were given Streptokinase (SK) or placebo between 3 and 6 hours after the onset of acute myocardial infarction (AMI). Left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR) and regional wall motion (RWM) were evaluated by equilibrium gated radionuclide angiocardiography (EGRA) at 3-5 weeks and 6 months after the onset of AMI. In the anterior AMI SK-group, the mean LVEF values rose from 0.37 at one month to 0.43 at six months, PER (end-diastolic volumes per second) from 1.76 to 2.00, and PFR (end-diastolic volumes per second) from 1.46 to 1.75 (p = 0.01, p < 0.05, and p < 0.05, respectively). In the anterior non-SK group no improvement was seen in any of the LV function parameters. Only a slight improvement was observed in the inferior AMI group, with no significant difference between the treated and non-treated patients. The regional wall motion analysis was in agreement with the global function data. In conclusion, SK treatment given between three and six hours after the onset of anterior AMI may result in some improvement in LV function, which becomes fully appreciable only after the complete resolution of stunning, i.e. after more than one month.

Aged↗
PubMed1993

[Decisive scintigraphic diagnosis in a case of Borrelia infective sacro-iliitis].

The authors describe one case of infections sacro-iliitis caused by Borrelia, where the diagnostic procedures by conventional radiology, computerized tomography and nuclear magnetic resonance imaging have not permitted the localization and the assessment of joint inflammatory disease. The bone "theree phases" scintiscan by 99m Technectium-methylene diphosphonate (99mTC-MDP) has made it possible to localize on left sacro-iliac synchondrosis a modification of radioactivity, due to inflammations. Next microbiological studies gave a positive result for borrelia. The authors finish by underlying the importance of the nuclear medicine methods in the screening of infective osteo-arthritis.

Adult↗
PubMed1992

Radionuclide assessment of left ventricular function in patients with myocardial infarction and diabetes mellitus.

The aim of this study was to compare left ventricular function, assessed by radionuclide angiocardiography, in 54 diabetics and 194 non-diabetics with acute myocardial infarction (AMI). The most meaningful results concern the inferior AMI group, whose left ventricular ejection fraction (LVEF) and regional wall motion were significantly lower in diabetics than in non-diabetics (LVEF was 44.2 +/- 11 vs. 51.6 +/- 9%, P less than 0.005; the regional wall motion score was 0.46 +/- 1 vs. 1.56 +/- 1, P less than 0.01, respectively), while no significant difference was observed in the anterior AMI group. However, in the group as a whole, the LVEF was 41 +/- 13% in diabetics and 47 +/- 13% in non-diabetics (P less than 0.01), the number of abnormally contracting segments was 2.0 +/- 0.9 and 1.5 +/- 1, respectively, and the wall motion score was 0.2 +/- 1.1 and 1.0 +/- 1.4, respectively (P less than 0.01). These data could be explained by an underlying cardiac dysfunction in diabetes, in addition to AMI. The more marked difference between diabetics and non-diabetics in inferior AMI might be related to the smaller infarct size in this group.

Adult↗
PubMed1990

Biomarkers and IL-2R in lung cancer.

A study of TPA, CEA and IL-2R serum levels was conducted in patients untreated with various histological types of bronchial carcinoma. A total of 43 subjects were evaluated. We have observed a significant correlation between serum levels and stage of the disease for both CEA and TPA markers, whereas for IL-2R an increase was shown for the all patients not correlated with stage.

Adenocarcinoma↗
PubMed1988

Two-dimensional echocardiographic evaluation of right ventricular ejection fraction: comparison between three different methods.

Twelve patients with chronic cor pulmonale due to chronic obstructive pulmonary disease have been examined with 2D echocardiography, performing four-chamber view by apical and subcostal approaches, and the right ventricular outflow tract view by the subcostal approach. These views have permitted evaluation of right ventricular volumes, and hence right ventricular ejection fraction, by the use of three different geometrical formulae: the biplane area-length method, Simpson's rule and the pyramidal method. The ejection fraction values obtained from each method have been compared to those obtained by equilibrium radionuclide angiocardiography. Four-chamber apical and subcostal views were satisfactorily recorded in 10 of the 12 patients (83.3%), and right ventricular outflow tract view in 8 patients (66.6%). No significant statistical differences have been found between measurements obtained from the three different echocardiographic examinations performed on each subject by the same operator, so demonstrating a satisfactory reproducibility of the technique. The highest correlation coefficient for ejection fraction was shown by Simpson's rule (r = 0.96, p less than 0.001), with a very narrow confidence intervals, while the r values for the biplane area-length method was 0.63 (p less than 0.05) and for the pyramidal method 0.50 (not statistically significant), with increasingly wider confidence intervals. The statistically significant difference between the three correlation coefficients demonstrates the higher accuracy of Simpson's rule for the determination of right ventricular ejection fraction.

Aged↗
PubMed1987

Angioscintigraphic assessment of arterial and portal liver blood flow: comparison with splanchnic angiography.

In order to validate an angioscintigraphic method for the evaluation of the components of hepatic blood flow, the results of angioscintigraphy were compared with splanchnic angiography in 25 cirrhotics. Two indices of hepatic portal perfusion and a splenohepatic arterial index were calculated. These were correlated with portal diameter and hepatic artery diameter, respectively. No correlation was found between grades of portal perfusion according Nordlinger's criteria and these indices. The method is very simple and could be applied to evaluate the changes of liver hemodynamics induced by drugs or shunt surgery.

Adult↗